Embed an OpenMOLE workflow in a task

A MoleTask encapsulates a whole Mole in a task. A Mole can form a complete workflow or part of its tasks and the
transitions linking them together. It may be useful to delegate entire Moles executions to the same remote node.
Another typical use case is to make you Moles and workflows more modular.

To encapsulate a Mole in a MoleTask, simply wrap it in the MoleTask builder:

// Define tasks t1 and t2
val moleTask = MoleTask(t1 -- t2)

In that case, the MoleTask's inputs are the same as t1's and its outputs are the same as t2's.